The present invention relates to lock mechanisms for electrical connectors.
The conventional lock mechanisms for compact, high-density electrical connectors include mechanisms such as shown in FIG. 5 of Japanese Patent Application Kokai No. 62-51170 (hereinafter "'170 patent") and FIG. 21 of Japanese Patent Application Kokoku No. 62-131487 (hereinafter "'487 patent").
The electric connector lock mechanism as shown in FIG. 5 of the '170 patent includes a pair of cantilever lock arms extending backwardly from the front ends of opposite sides of an insulating housing. A lock projection is provided in the middle of the outside of each lock arm to engage the lock member of a mating connector. This lock is released by pressing the rear ends of the lock arms with fingers to flex them inwardly so that the electrical connector is pulled out of the mating connector.
The electrical connector lock mechanism as shown in FIG. 21 of the '487 patent has a structure substantially identical with and functions in the substantially same way as the above lock mechanisms. The rear end of a lock arm (latch) in the lock mechanism is inserted into a groove of a rear housing for protection.
The lock mechanism of the '170 patent has the following disadvantages.
(1) The lock arms of a plug housing for a compact, high-density electrical connector is so small that it is difficult to handle the grips with fingers.
(2) The grips of the lock arms are so small that it is difficult to pull the plug out of the mating connector by using the lock arms.
(3) If the lock arms are extended outwardly to mitigate the above problems, the demand for miniaturization is not met. These extended lock arms tend to break down at their joint portion because of a concentrated load. These extended lock arms tend to be entangled with each other during transportation between production stations, blocking a stream of production.
(4) The lock arms directly extending from the housing are made thin and not protected. Consequently, they are liable to deformation or damage by an external force, etc.
The lock arms of the '487 patent has disadvantages similar to the above except that the rear ends of lock arms are protected in the grooves.